


Body Swap Fuck

by Kanimay



Series: To Many AUs So Little Time [1]
Category: Echotale - Fandom
Genre: Alphys does experiments, F/M, Smut, heat - Freeform
Language: English
Status: Completed
Published: 2017-12-29
Updated: 2017-12-29
Packaged: 2019-02-23 08:12:44
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,179
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13185990
Author URL: https://archiveofourown.org/users/Kanimay/pseuds/Kanimay
Summary: You and G switch bodies, thanks Alphys. <_< G has his heat while you are in his body and he has to help you through it. This is a revised version of "Fuck Yourself with his Body" one of my first smuts ever.... so this one is better... promise.





	Body Swap Fuck

Lazy around the skeleton brothers house was your favorite pass time. You watch tv, play games, have joking conversations and in depth conversations, even cook with Paps. When the monsters came above ground 4 years ago you were walking your dog till they ran off, chasing after them they run into a small child you knew all to well. Frisk, said child was being attack with licks from your dog as a few monsters laughed at their struggle to get up. You had to stifle your own laughs as you ran over to the dog "Sorry." You re-leashed the dog before pulling it off the child, they sat up a slobbery panting mess "Long time no see Frisky. I was worried, but I'm glad to see you're ok." You kneeled down and hugged them, not minding the slobber. 

After that they introduced you to their new family and friends. You explained that they were your little adopted sibling that had went for a walk after school, you had known but when they went missing you went hunting to find them but never could. The police gave up 2 weeks after the report was filed and you had spiraled into a deep depression deeming yourself a failure at being an elder sibling. Toriel then adopted you as well as Frisk. You love your new monster family and friends. 

Back to the present you were chilling on the couch with G Sans. Though he preferred G,you two had just got back from dropping Frisk off at school and decided to channel surf. Nothing was ever one in the mornings, you hit G with a throw pillow lazily, not really sure why, just felt like it. Just as you reeled the pillow back for another hit your phone buzzed. You dropped the pillow mid throw and grabbed it, the pillow had hit his ribs and he instantly took it and placed it to his other side, away from you.

 

Alphys: A-are you busy?

You: No... why?

You and Al were pretty close friends. Both being anime addicts, you binged together and ranted together.

 

Alphys: C-can you... uh come t-to the lab? M-maybe bring s-someone else to?

You narrowed your eyes at the screen, she normally wouldn't request you bring someone if it was a spontaneous sleepover. "Hey GG, wanna go to the lab? Alphys asked." He groaned at the nickname before flicking the tv of "Sure. Did she say why?" You shook your head as you told her you would be there in a few and you left the house.

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

In the lab you sat at her table... totally not a medical bed... those weren't wheels... it was totally a table. Undyne was sitting next to you, G across from you. The little lizard women took her leave to get whatever. When she came back in she had a few veils and set them on the table. 

You all looked at them questioning them mentally "What gives babe?" Undyne gestured to the items "T-there some s-stuff I was working o-on. T-two are b-body swappers, 1 i-is a gender s-switcher." She explained. One liquid was bright red, the other two a dark purple. "I-I want y-you guys to t-try them for me." She fiddled with her claws, she was always nervous about her experiments. Undyne grabbed the bright red "I'll do anything for ya, let's go you two!" She gulped the liquid with pure enthusiasm as you and G grabbed the other veils hesitantly.

Black covered your vision as you blacked out. You heard your head hit the table before all your senses shut off. 

"...ns...."

"....ans...."

"SANS!"

Someone shook you and shouted with a deep voice "m'why you calling me Sans?" Everyone only ever called G that when they were angry or worried... did something go wrong? 

You lifted you head, it was fuzzy, a blue and red blur was next to you. "I-I guess they g-got swapped." Alphys mumbled as your vision cleared. Undyne was indeed the other gender... she was buff and tall, Alphys would often blush a deep red when looking at her... him? Was this permanent? 

Just as you were going to question it a soft groan came from across the table. You looked to see your body slowly lifted its head and shaking it lightly "My head." It whined. As their own vision cleared they looked at Undyne with shock before moving to you. This was odd "ALPHYS TELL ME THIS IS NOT PERMANENT!" They yelled towards the short lizard, she jumped and shook her head. "N-no! It will l-last a few hours!" She squeaked. 

After a few moments G started checking your body out, he was shorter then he was use to... and had obvious things he wasn't use to. "Please stop groping me!" You slammed your head on the table as he squeezed your breasts and bouncing them up and down with an amused smile "Can't help it... so weird in a good way." He stopped before looking down your pants "Stop checking me out!" You slammed your hands on the table as a loud moan was heard a few doors away... right the other two had left for... reasons.

Both your faces blushed before you bolted out of the lab. 

You two slowed your running to a fast paced walk before calmly walking down the sidewalk. G was behind you, not being use to shorter legs. He kept watching his reflection in windows till a familiar sound hit you now nonexistent ears. You looked over your shoulder to see your body flush a dark red grabbing at your stomach "Hungry?" You questioned as he nodded "What the hell was that?" He walked next to you "Your stomach." You laughed as you entered Grillbys. 

You took Gs' normal spot as he took yours. The fire elemental showed up, you ordered fries, as he left for your order you caught G looking down your shirt. You smacked him over the head he let out a grunt before rubbing the spot "Don't hit me... just looking." He put his elbows on the table "Well you have nothing for me to look at or fondle so knock it off." You growled.

Grillby set the fries down in front of you and looked you both over "You both seem off... is everything ok?" Leave it to him to notice his most loyal costumers are off "Nah Grillbz. We are fine." You waved his worry off as G add in silence. He nodded and walked off to take care of other patrons. You looked the fry over before tossing it into your mouth... it just fell down your throat... how the hell does he eat like this!? You need your tongue back! You heard a snort next to you, you looked to see him covering his mouth and shaking with laughter "Bite me." You grumbled before grabbing a handful of fries and tossing them, feeling them all fall down your nonexistent throat was horrible. You visible cringed as G finished his own fries.

You stayed and talked to each other as well as Grillby, when it was late you walked back to Gs. Sun was set and the sky was dark as you entered the house "This has been an odd day." You grumble closing the door behind the short little human... "Fuck I really am short!" You suddenly realize, for most of the day he had trailed behind you, or sat near you. You couldn't get a real show of the difference "You just now noticing doll?" That nickname felt odd coming from your mouth "Shut it shorty... go change into your PJs." You plopped onto the couch as he smirked "Sure." He made his way up to the bathroom.

...

...

...

...

...

You bolted from the couch when sudden realization hit you. Skipping a few steps as you ran you busted the bathroom door open to see G bent over pulling his pants off, he was already stripped to your bra "Close your eyes! I'll do it!" You slammed the door shut "You are no fun." He pouted letting go of the pants letting them slide of your legs. "Close. You. Eyes." You went through your bag to find some fluffy PJs and a tank top.

You unhooked your bra before sliding the tank top on with no real help from G. He was being a child. When you went down to the panties he peeled his eyes open "Do you not sleep in panties?" That smirk was strictly lewd as you narrowed your eyes "I wear clean panties to bed... eyes." You huffed before pulling them down his legs. Seeing your body from this angle... why did you body just get hot all of a sudden. You shook your head of the thought, no way lewd thoughts like fucking your own body with his was going to sneak into you head. You finished dressing him, he shivered at the pants "Something wrong?" You stood up as he looked at his reflection "Your body is really sensitive." He mumbled as you left back to the living room.

You two watched tv for a few hours before you felt sleepiness settle in. Announcing your were going to bed he hummed before taking the remote. 

Once in his room you stripped of his thick comfy jacket, boots and belt before plopping onto the bed. This was normal... sleeping on his bed. It's where you normal slept when over. It was a queen size, plenty of room. Nice thick covers made of silk, pillows that you just could not stop cuddling once unconscious. 

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

You woke up feeling warm tossing off the covers seemed to make it worse. Your pants felt tighter and painfully so. Unbuttoning gave some relief but not enough so you just took them off and kicked them to the side of the bed. Tossing and turning made whatever was wrong with you worse. You assumed the swap was wearing off, you checked the time to see it was 4 AM. Where was G? Was he still watching tv?

You pushed yourself up, all over you felt hot. Pushing through the door you made your way downstairs to see you body still watching tv. "G... bed." You mumbled standing on the last step, leaning over the railing. There was a scent... it was nice and your mind began to cloud. It was so nice, like really sweet but not over barring. G looked over at you his eyes narrow before standing in a panic "Are you ok!?" He rushed to your side, putting his hand on your ribs and spine, you let out a soft groan "Shit... I thought it would wear off before my heat." He mumbled helping you up the stairs. Heat? Like animals?

He helped you back into the room and on the bed. Though you were just sitting there. Your body was to hot, if you were in your original you would defiantly need to go to the hospital for over heating. "W-whats going on?" You panted out. There was a yellow glow behind the boxers you kept on. G lifted your chin to look at him "You're in heat. My heat... fuck that sounds strange. Either way you need to stay in bed." He tried pushing you down.

Your mind became clouded screaming to pound something into the mattress under you. You grabbed Gs wrist pulling him down and whined "N-need... you." He frowned at your plea "You can't. You wont be able to control yourself if we started, it lasts days." He tried to pull away only for your hold to tighten. "Please... tie me up o-or something... I need you." You panted grinding your hips against the leg that was between yours. The friction was great but not enough. 

His own will fled "Fine... stay. I will be right back." He pulled away, your grip loosening once he gave his consent. He walked to his closet, rummaging around before coming back with a thick scarf. "Scoot onto the bed more." He ordered, you did as told and sat in the center, he had crawled up the bed taking your wrists gently before tying them tightly. "Lay down." He put his hand on you pushing you back, to which you obeyed.

He kissed your teeth quickly before trailing down your jaw and neck, sucking anytime you would buck up, his hands slid down your ribs. Dipping between to rub the underside before leaving, one hand rubbed the bulge behind the boxer fabric as the other started jerking your spine. You moaned and whimpered under him as his tongue licked your clavicle. He rubbed harsher as he lowered his body down yours. he left butterfly kisses on your spine as he pulled the boxers down. Your erect cock sprung out, you gave a sigh at the relief then shuttered at the sudden cold. 

"This... is going to be an experience." G grumbled before rubbing the member, it was long, about 8 inches and thick, he rubbed harder as it started to lick pre "Pleease... y-your mouth." You brought your bound hands up to grip the pillow above your head. "Seriously!? No way!" He looked at you.  
You face was flushed yellow, your eyes pleading for more. Your body withered under him. With a roll of his eyes he slowly lowered before taking the tip into his mouth.

It was so warm your hips bucked into it, he held them down giving you a scowl before bobbing his head. You arched your spin and moaned. "F-fuck~!"

He brought one hand up to jerk your spine with his bobs, taking more of the cock into his throat. You were a panting, moaning mess beneath him. 

A few more licks and sucks and you came undone. You grabbed at his hair holding him to your cock as you spilled into his mouth. He let out a moan as you gave a few careful bucks. When you were finished you let him pull away, he had some leaking down, he licked it clean off with his tongue looking at you with a clouded gaze "I want you to do something for me." He purred before getting off the bed. You watched as he slowly, teasingly slide his tank top off over his head. You really did have a nice rack. He moved down to the pants, leaving him in just panties, he crawled back on the bed straddling your hip "I want you to wreck your own body." He mumbled into your ear... or at least where they would be. 

You whimpered "I will! I will just let me inside you!"

He smirked before leaning forward, giving you a nice few of your own chest while he took the panties off. You cock brushed against his ass as he tossed them to the side. Slowly bringing his fingers down his stomach to his core, he rubbed the sensitive bud while you watched. "Do you ever touch yourself, thinking of me?" He moaned out as you nodded "Thinking of me fucking you.. pounding into your little pussy?" He brought his other hand down to play with the folds.

You moaned at the sight, not caring that you just confessed you masturbate to fantasies of him and you. He inserted 2 fingers "Damn... so wet." He panted while rubbing himself off. 

You watched, unable to do anything but watch. His rhythm became sloppy, he was getting close, you could smell nothing but his arousal from him. "So tight and sensitive!" He panted out bucking his hips back onto your cock "Why haven't we actually fucked before?" He pulled his fingers out to show they were dripping with juice. He licked them clean moaning at the taste "Fuck you taste so damn good... I am so eating you out when I get my body back." He claimed as he gripped your member "Ready for the real fun?" You nodded giving a moan at the grip.

He lined up before sinking down carefully. You both moaned in unison. Your body was so tight and felt so good around his cock. He placed his hands on your ribs before sink all the way to the hilt. He shuttered and leaned forward "F-fuck... so big." He moaned.

A few moments of adjusting and he began to grind. You bucked at the movement before he moved up and down slowly, "Mooore." You panted out looking to where you were joined. "Am I always so greedy when in heat?" He chuckled before giving you what you wanted. He bounced harder and faster. He picked the pace up then slowed down edging you on and on, you followed with your own bucks before you came once more. Filling him full, you moaned and kept bucking, slowly down once your peak ended. He was untying you as your cock hardened once more inside him, "Fuck me." He groaned as the scarf was tossed.

That was all you need, pushing him back onto the bed before pounding him quick and hard. He wrapped his arms around your shoulders, screaming and moaning. 

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

How long did you two bone? You had no clue. When you woke up you felt nothing but sore and wetness between your legs... wait where is G? You two passed out days later once his heat ended... your body swap ended a few hours after the first session, you had passed out prefuck and woke up to him pounding and growling. He wished you good morning before switching the position to doggy. He bite and sucked at whatever he could and gripped your hips and sides, so many bruises.

As you came out of your sleepy fog you felt something wiggle inside you. You groaned and bucked forward, looking down to see him eating you out. He saw your gaze and winked at you before plunging a few fingers in, making a beckoning motion with them sending you over the edge. He helped you ride it out before pulling out "Morning babe. Sleep well?" He crawled up and laid down next to you "Sore." You mumbled rolling over to face away from him. 

The gravity of the situation came crashing down on you. You two fucked... a lot. And it was great. But how does your friendship come back from that? Did you just lose him as a friend? As you were having a mental spiral down you jumped when you felt an arm gently wrap around your bruised side. "Let's just stay in bed, huh? I am exhausted and I know you are." He chuckled nuzzling your cheek.

"How are you not weirded out by this?" You mumbled, you felt his arm move to where his hand was laying on your side softly "Because I just fucked a hot little human." You could feel his smirk on your cheek "Be serious for once damn it." You flicked his forehead the best you could without seeing it. "I am. Now go to sleep. I don't want a grumpy girlfriend." He gave you a skellie kiss before trying to sleep.


End file.
